Polysiloxane isocyanates



arrears Patented Apr. 20, 1965 United States Patent A further object is to prepare compositions that, when vulcanized in a confined space, do not undergo reversion.

These and other objects will be apparent from the following description:

This invention relates to an organosiloxane isocyanate represented by the following structurez 3,179,622 POLYSILOXANE ISOCYANATES Loren A. Haluska, Midland, Mich, assignor to Dow Corning Corporation, Midland, Mich., a corporation of Michigan 5 No Drawing. Filed Mar. 26, 1962, Ser. No. 182,663 14 Claims. (Cl. 260-465) This invention relates to novel and useful orgauosiloxaneisocyanates that are storable, which vulcanize by eX- posure to moisture without requiring heating.

The utility of silicone compositions that can be vul- 15 ig monovalent Hydrocarbon or halohydmearbon md' I I 2 i g Withoui i Is Well i f fi Wlde 118.6 W is a divalent organic radical having at least two carbon t ese maiena S m cmPmsrceany 0 t 6 comp atoms therein, connected to silicon by a silicon-to-carmom that will so vulcamze are of the Wig-package type bon bond and to the remainder of the molecule through that there are two portions i when mlxed will there- 0 another carbon atom of the radical andselected from y yulcanize said process beginning immdiateiy upon 0 the group consisting of hydrocarbons, hydrocarbon mlxmg so that once the tWO.c0mpOnentS i the thioethers, hydrocarbon esters, and hydrocarbon tertiresulting blend must be applied where desired within a my amines Short else the Immune i R is a divalent aliphatic hydrocarbon radical containing Recent room temperature vulcamzmg slhcones that are r 2 to 4 carbon atoms therein such that no carbon atom available are of the one-package type. These materials Shall havemore than ens Oxygen atom attached there do not vulcanize until removed from their storage conto tainer. Thus, theunused portion is not wasted unless it X should be removed from its container. Oftenthese materials are stored in vessels suitable for use with caulking 0 f f i guns and similar equipment. It is this latter type of room N, -CN-; C-N- temperature vulcanizing material to which the composiwherein R is as above d fi d non of H113 mVent 1On 1s slmflar' Y is a divalent hydrocarbon radical free of aliphatic un- Each 0f P known one'component systems has saturation and containing at least four carbon atoms shown some disadvantage. The system based on acetoXy- 35 therein siloxanes or acetoxysilanes shows corrosive activity due a is an integer including 0 to the formation of considerable quantities of acetic acid b is 1 as a by-product of the vulcanization reaction. Recently m is 0, 1 or 2, disclosed systems based on alkoxysilanes or siloxane oX- n is 0 or 1, imes produce alcohol or alcohol derivatives during vul- 40 is 0 to 3 inclusive canl'zafion which alcohols in a confined sysiem are known p is an integer such that the sum of all said p values in the to cause at elevated temperatures reversion (depolyml l averages at least that givenby the equation erization) of the siloXane chain structure. (sum of all p) 5(32m) wherein m is as agove The instant compositions vulcanize by exposure to fi i i moisture. The i only by-product' is CO a gas. Both r CO and moisture diiiuse easily through siloxanes, allow- The composmons of this uiventlon can have any of ing thick section or confined cure without corrosion or the l u e s A represents reversion. I? 1? In addition, v ulcanizates from the instant composition have higher tensile strength than analogous vulcanizates W (OR Xbb N Y N-C O from the above stated silicone systems, either one com- R2 R2 ponent or two component. Also, the urethane-type cross- (1) A SI(OSDDA link formed by the vulcanization process imparts somewhat improved solvent resistance to the rubber. f"

Further, the product of this invention is useful wher- (2) RZSiKOSDPA], ever organic urethane compositions fail on account of poor resistance to moisture and low-temperature embrittlement. Both of the aforesaid limitations are overa A-Si[(OSi) A] come by the instant invented compositions. B One object of this invention is to prepare new organo- I siloxane isocyanates. K DD b Another object is to prepare organosiloxane isocyanates that can be stored without undergoing change or decomposition. (5) A )p ]a Another object is to prepare organosiloxane isocyanates that vulcanize when exposed to moisture. (6) SH (0 A1 Another object is to prepare organosiloxane isocyanates that vulcanize to a rubber when exposed to moisture which when vulcanized are strong and moisture resistant.

Still another object is to prepare compositions that, upou vulcanization, do not produce corrosive by-products.

wherein In structures 1 and 2 the minimum average total of p is 5; in structures 3 and 4 the minimum average total of p is 15; and in structures 5 and 6 the minimum average total of p is 45.

When the minimum average total of p in the molecule is less than the stipulated minimum as illustrated above, the resulting vulcanizates do not have flexibility, or if flexible (due to a large organic modification) do not have the desired low temperature flexibility of the compositions of this invention. In addition, moisture resistance of compositions containing less than the minimum average total p value is impaired thereby.

For the purpose of this invention R can be any monovalent hydrocarbon radical such as alkyl radicals such as 7 methyl, ethyl,'isopropyl, tertiaryarnyl and octaclecyl; al-

kenyl radicals such as vinyl, allyl, methallyl, and octadecenyl; alkynyl radicals such as ethynyl and butynyl; cycloalkyl radicals such as cyclopentyl and cyclohexyl; cycloalkenyl radicals such as cyclopentenyl; aralkyl radicals such as benzyl and beta-phenylethyl; and aromatic hydrocarbon radicals such as phenyl, xenyl, naphthyl, anthracyl, tolyl and xylyl. R can also be any monovalent halohydrocarbon such as chloromethyl, bromophenyl, 3,3,3-trifluoropropyl, Z-chlorovinyl, ot,o,rxi1'iflll0l'0- tolyl, a-chloro-a,[3,,8-trifiuorocyclobutyl and bromoxenyl. In any given composition R can be the same or different within the composition. This will be understood more clearly in the description of the preparation of the instant composition.

For the purpose of this invention, W can be any divalent hydrocarbon radical such as alkylene radicals such as alkenylene radicals such as CH=CHCH CH CH=CHCH and CH3 cn=h 0H2 cycloalkylene radicals such as cyclobutylene, cyclohexylene and structures such as arylene radicals such as phenylene, naphthylene, biphenylene and tolylene; and aralkyl radicals such as CH2C6II4CH2, -C5H4CI{2CGH4- and any hydrocarbon tertiary amine radical such as R can be any divalent aliphatic hydrocarbon radical such as alkylene radicals such as r '-CH2CHQ CH2UH,

alkenylene radicals such as CH CH=CHCH and alkynylene radicals such as -CH2CECCH2-.

Y can be any divalent hydrocarbon radical free of aliphatic unsaturation such as, for example, aliphatic radicals such as --(CH CH CH(CH (CH -CH CH (CH CH CH CH (CH CH CH CH CH C (CH and (CH cycloalkylene radicals such as As stated above, the total of p in the formula for the instant composition is 5(3 else the composition, when vulcanized by exposure to moisture becomes too brittle and/ or weak. Any composition with more than the so stated minimum average total p will function as the composition of this invention. Where it is desired to employ a pourable composition, it is preferred to use linear compositions (structures 1 and 2 above) wherein the total averages 20 to about 200.

The compositions of this invention are best prepared from organosiloxanes containing silicon-bonded hydrogen atoms, of the structure En R1 RmiKO S i) H] l-m-u wherein wherein R, m, n and p are as defined for the composition of the invention. The preparation of these organosiloxanes is well known in the art. They may be prepared, for instance, by the hydrolysis of appropriate amounts of RSiCl R SiCl RHSiCl HSiCl SiCl and R HSiCl, appropriate selection being made therefrom to obtain the particular structure desired. Thus it can be seen that R in the siloxane can be selected to be any monovalent hydrocarbon or halohydrocarbon radical or any combination of the said radicals, determined by the choice and amount of chlorosilane selected. Other methods of preparing the above siloxanes, also well known in the art, allow a similar freedom 'of choice. In addition, the siloxane above can be a mixture of siloxanes of I it The reaction can be carried out by any of the methods know for this reaction, with or without catalysts in the presence or absence of a solvent, or at atmospheric or different pressure. and

or CEC can be used, although it ispreferable, but: not necessary to use 'a small excess of say, 10 percent or" the unsaturated compound This excess is easily re-- moved, as it is usually quite volatile. In cases wherein the unsaturated compound is not volatile, it is preferred touse stoichiometric amounts.

Stoichiometric quantities of ESiH' The product of the reaction above is an organosiloxane wherein all the silicon-bonded hydrogen atoms are replaced by radicals of the formula W(OR),,X'H, wherein W and R are as previously defined, X is -O, S

The product above is then reacted with an excess of a diisocyanate of the formula O=C=N-Y-N=C=O wherein Y is as hereinbefore described by mixing the two materials. While it is not necessary to do so to cause reaction, warmingthe mixture to up to about 100 C. will hasten the reaction. Excessive heat should usually be avoided, else extensive crosslinking can result in addition to the desired reaction with some reactants. The reaction equation is as follows:

EsrWwR'),X'H+0=o=NYN=o=0 the reaction produces CO with the net result equivalent to loss of the said radical:

II H l 2 4 II t It is in this instance that b in the composition of the invention is O. In all other cases the reaction is one of addition as shown, and the said b is 1. It is clearly seen that in all other instances X becomes X. Subsequent to reaction any unreacted diisocyanate can be removed by volatilization. The product of this last reaction is the invented composition.

An alternate. method of preparing compositions of this invention is applicable with certain organic compounds containing active hydrogenthat will add across the double-bond of an alkenyl group. One example of such a compound is thioglycollic acid. The starting siloxane can be one containing an average of two to four alkenyl groups per molecule, of the structure rn )D ]4-'mn wherein R, m, n and p are as previously defined and I is a monovalent alkenyl radical such as vinyl, allyl, methallyl, and cyclopentenyl. Illustrating with thioglycollic acid, the reaction between said acid and the said siloxane above wherein J is vinyl, induced by, for example, ultravioletlight, produces groups Wherever I occurred in the siloxane of the following structure:

The product is converted to the composition of the invention by reaction with a diisocyanate as stated in the description of the previous method of preparation.

A third method of preparation of the instant invented compositions is by preparing a siloxane copolymer of the formula Rmsi[(0s i),,L]i m-n wherein L has the composition -W(OR),,XH, and all symbols used herein are as previously described. Copolymers of this type can be prepared for instance from the hydrolysis of mixtures selected from R SiCl RLSiCl R LSiCl, RSiCl and SiCh, and LSiCl Examples of such chlorosilanes are reported in various places in the literature. Other hydrolyzable silanes are of course operable in place of or in conjunction with the chlorosilanes just shown.

The said cohydrolyza'te can be convertedto the composition of the invention by reaction with a diisocyanate in the before-stated method.

The product of this invention will vulcanize when exposed to moisture, somust bc'stored away from said moisture to prevent the said vulcanization. So stored, it is stable for an indefinite period of time, atleast greater than six months at ordinary temperatures. -While the addition of a catalyst to vulcanize the composition is not necessary, it can be used if desired. Such catal sts as are commonly used. for polyurethanes such as amines and organotin compounds may be used. If desired, a quantity of organic dior polyisocyanate can be added to the material of the invention to hasten its cure.

The invented composition can be used alone, or, if desired, such additives as fillers, such as carbon black, fume silica, hydrogels, xerogels, metal oxides, clays, powdered metals, mica, asbestos and the like can be added. In addition, pigments can be employed to obtain a desired color. If desired, additives such as for reducing compression set can also be employed. The above additives may be added either during or after the preparation of the polysiloxane isocyanate. Where maximum storage stability is required, these various additives should be essentially free of moisture. However, where it is desired to cure the mixture shortly after the addition of one or more of the above materials, moisture therein will serve to facilitate the said cure.

The compositions of this invention can be used wherever roo1n-temperature-vulcanizing flexible materials find application wherein extreme heat stability is not required. These include, for instance, molding, potting, encapsulation, sealing, leather treatment, paper treating, and fabric treatment. The instant compositions are especially useful where freedom from corrosion and/0r reversion is required. Where low-temperature flexibility is required these materials will also find use.

The following examples are illustrative only, and should not be construed as limiting the invention, which is propertly delineated in the appended claims. In the examples the symbol Me represents the methyl radical.

Example 1 A mixture of 74.7 grams of methyltrichlorosilane, 6198 grams of dimethyldichlorosilahe and 141.9 grams of dimethylhydrogenchlorosilane was made in 3000 grams of heptane and hydrolyzed by addition to an excess of water. The hydrolysis product was neutralized with sodium bicarbonate, washed, dried, filtered and the heptane removed by volatilization. The fluid was equillbrated by mixing with one percent by weight (based on the total weight of fluid) of 15 percent fuming. sulfuric acid and stirring for 24 hours at room temperature. The sulfuric acid was then removed by water washing the fluid, and following a stripping to 180 C. at 2 mm. of mercury; 220 grams or" a siloxane fluid was obtained having a viscosity of 98.5 cs. at 25 C. of the average formula A reaction vessel was charged with 59.8 grams of allyloxypropanol, 140 grams of xylene and 1.7 grams of a solution containing :1 percent platinum as H PtCl in dimet hylphthalate. This m'mture was heated to reflux to remove any water in the system. Then 6379 grams of the siloxane fluid described above were added at such a rate that the temperature was maintained above 135 C. The reaction was suflicicntly exothermic that external heat was needed only toward the end of the addition of the siloxane fluid. Thereafter, the mixture was refluxed an additional 24 hours to complete the desired reaction. The product was decolorized with activated charcoal, filtered, and devolatilized to C. at 0.4 mm. of

phthalate.

7 grams of the siloxane fluid described above were added The reaction mixture was heated an additional 24 hours at a temperature of mercury. There was obtained 653.6 grams of a modified siloxane fluid having a viscosity at 25 C. of 171 es. of

the average formula Me; Me: Alia MesiuosimosuounaoGHZOHOHn A 562.2 gram portion of the fluid above was mixed with 39.6 grams of toluene diisocyanate in a dry nitrogen atmosphere. The mixture was heated to 70 C. for four oours to hasten the reaction. There was obtained a clear pale yellow fluid as the product of the formula Mei Mez Me (I? IEII I T=O=O A portion of the product was mixed With a catalytic amount of dibutyltindilaurate and allowed to cure 3 days at room temperature. The rubber so obtained had a hardness (Shore A) of 42, a tensile strength of 318 pounds per inch squared and an elongation of 210 percent. Example 2 A mixture of 2500 grams of octamethyleyclotetrasiloxane, 67.0 grams of tetramethyldihydrogendisiloxane, 36.1

grams of a hydroxyl endblocked methylhydrogenpoly- III iris: MeSiKOSDss h A reactor was flushed with dry nitrogen and thereafter charged with 44.1 grams of tert-butylamino-ethylmethacrylate, 240 grams of Xylene and .0139 gram of platinum added as a 1 percent solution of H FtCl in dimethyl- The mixture was heated to reflux and 5,925

slowly over a period of 2 hours.

135 to 140 C. after which the solvents xylene and dimethylphthalate were removed by stripping the product to 140 C. at 2.5 mm. of mercury. The yield was quantitative, a modified siloxane fluid of the average formula:

Mea

C Me Me Men Me O C lrtea (3 ca Example 3 tetrasiloxane, 67.1 grams of tetramethyldihydrogendisiloxane and 15.5 grams of percent fuming sulfuric acid.

There was obtained a clear fluid siloxane having a vis cosity of 47.6 cs. at C. of the average formula III lriez V MezSi(OSi)4iH A 328 gram portion of the above siloxane fluid was added to a mixture of 34.9 grams of allyloxypropanol and 2.0 g. of a 1 percent H itCl solution in dimethylphthalate heated to 128 C. After complete addition of the siloxane, the reactants were stirred at 125 to 135 C. for 24 hours, and thereafter stripped to 1 mm. of mercury at the above temperatures. There was obtained a modified siloxane fluid having a viscosity of 93.3 cs. at 25 C. of the average formula Toluene diisocyanate (22.5 g.) was mixed with the modified siloxane fluid above (181.5 g.) under dry conditions for 3 hours at to 84 C. There was obtained a quantitative yield at a clear fluid having a viscosity of 495 cs. at 25 C. of the average formula Me: Me

ILT=C=O z A portion (22.2 grams) of the above fluid was mixed with 0.153 gram of dibutyltindilaurate and allowed to cure. After 24 hours there was obtained a tack-free rubber, which after five days had a tensile strength of 539' pounds per square inch and an elongation 0 1 347 percent. The rubber was flexible at Dry Ice temperature (-78 0.).

Example 4 (a) A modified siloxane fluid (1649.9 grams) of the average formula l\le l\lic I'IO (6132051 0)11.2( Hz)3Sl(OSl)5,g(CHz)g(O CI'I2OHz)11 zO1'I was reacted with 407 grams of toluene diisocyanate at 80 to 82 C. for 3 hours. The product was a fluid product of the average formula Nlez Mez In a reactor were placed 108 grams of perchloroethylene and 8.0 grams of toluene diisocyanate. These materials were mixed at room temperature while slowly adding grams of the modified siloxane fluid prepared as above. The reactants were stirred an additional two hours after complete addition. The product was stripped to 100 C. at 0.1 mm; to remove the unreacted toluene diisocyanate yielding the polysiloxane isocyanate of the structure:

El) Me Me O C =N A sample was then cured by heating 24 hours at 80 C. The cured product was a soft rubber.

To C (Me)s O H a tensile strength of 981 p.s.i. and 187 percent elongation.

(d) A solution of 14.62 grams of the product in a and amaze 9 it) 2.14 grams of 4,4methylene-bis(Z-chloraniline) in 16.76 endblocked 3,3,3-trifiuoropropylmethylpolysiloxane liuid grams of toluene was poured into a flat mold and exposed of the average formula to the atmosphere. After two days the toluene had evaporated leaving a tack-free elastomer having a tensile strength of 1,086 p.s.-i. and an elongation of 232 percent. HO SiO H (e) A mixture of grams of the product in a, 3 grams 1 2 of powdered magnesium oxide and 3.5 grams of lamp- 1 t black was exposed one week to atmospheric moisture. The sample had cured to a strong rubber. CFa 9 Example 5 10 With vigorous mixing, (2) 78.9 grams of 1,2,2,4-tetra- Amixture was made of 525 g. of adirnethylpolysiloxane methyl-2-silylpyrrolidine were slowly added and the refiuid of the structure action allowed to proceed. The reaction mixture became Me2 Meg M02 hot during the reaction, reaching a peak temperature of HOsKOSDmOSiOH 55 C. After complete addition of (2) external heat was applied to maintain the temperature at 55 C. for one and gof 1,2.2,4tetramethyl-hflylpyrwhdme, f me hour. Finally, the product was heated to 120 c. at 2.4

Structure mm. of mercury to remove any volatile material, cooled MezSi-OHz and filtered. The yield Was quantitative, having the CH Me 29 average formula Me-I TO 2 Lille Lite ltl/ie Me M82 ll/le ltte whereupon there was lmrnedlate react1on to produce a H N CH2CHCH2SiO sio A oHgoHoHhNqq modified siloxane fluid of the structure I hide Mel M92 M62 Mel Me: Me III MeNCHgCHOH2SiOSi(OSilmOSiOSiCHzCHCHzNMe CFa 1n The excess pynrolidine was removed by stripping to 180 at 0.5 mm. of mercury. A 100 gram portion of the product from above was A 375.8 gram portion of the above product was mixed added to a mixture of 34.7 grams of toluene diisocyanate, with 37.3 grams of toluene diisocyanate and 175 grams 134.7 grams of methylene chloride and 100 grams of of dry toluene and heated to about 90 C. for about 3 perchloroethylene at such a rate that the temperature in hours. The toluene and excess toluene diisocyanate were the reaction was maintained below 30 C. The methylremoved by stripping the product to 152 C. at 1.1 mm. ene chloride, perchloroethylene and excess toluene diisoof mercury. There were obtained 38 6 grams of a clear cyanate were removed by heating the product mixture to fluid having a viscosity of 23,330 cs. at 25 C. of the C. at 1.2 mm. of mercury. The product was a structure viscous clear fluid of the structure Lite 1\'te Elie; Elie Brief!) 1'1 sit OSIi OSiCHzCHCHz-N-C- Q-Me CH2 CH2 l l =0 r w on on 4 2 Iii C) Bile lYIe l |/Ie2 l\|dez filler Ill/lea Alder Itte Elle $1) 1? MeONG-NCH2CHCHzSiO-Si(0SDHQOSi-O-SiCHgCHOHz-NON-Mti o=C=1 I N=o=0 A sample of this fluid cured to a tack-free rubber on 50 which set up to a hard flexible plastic material on exexposure to atmospheric moisture for five days. Another posure to atmospheric moisture. sample, mixed with 035 percent by weight of dibutyltindilaurate cured in one day to a tack-free elastorner with a tensile strength of 193 pounds per square inch and an elongation of 173 percent. When a modified siloxane fluid of the average formula Example 7 is reacted with a diisocyanate of the formula Example 6 Into a reactor were placed (1) 348 grams of a hydroxyl O=C=NoHP N=C=o as in Example 1, there is obtained the polysiloxane isocyanate of the formula l r e it t OSIi OSIi 01103 0011202! mooN- ;H2C N=o=o 9 which, when mixed with 3 percent by weight of 4,4- which results in a polysiloxane isocyanate of the structure methylenebis(2-chloroaniline) will cure to a tough rub- Me Me Me2 Me Me O H bery solid. l H l H Example? S|1 0S1 -OS1CH2CHO z-NCN- A Me A vinyl endblocked dimethylpolysiloxane fluid is ob- 1112020 tained when 1480 grams of octamethylcyclotetrasiloxane and 9.3 grams of divinyltetramethyldisiloxane are heated together with 0.25 gram of powdered KOH for several 13 -2 hours at of the Struciure (b) A copolymer of allylrnethylsiloxane and cycloo hexylmethylsiloxane, of the average composition MezSi[(OSi)45Vi]2 Me Me When a solution of the above polymer and thioglycollic HO H acid in toluene is bathed with ultraviolet light at room temperature for about 18 hours, there is formed a modi- CH2CH=CH2 3 fied polysiloxane fluid of the structure CH2 CH2 Allen (I) \CH5"CH2 .49 MezsmoSi)CHZCHZ SCHZCO"H] which gives a polysiloxane isocyanate of the structure t r l w e r i Me: r l l t Me-C NCN-OH2CHCHiSiO SIiO etc 1 S iCHzOBOHr-NO-NC Me OO I I E E I 1 IC-0 Hfih Log: ornJ w CH2 3 CIh-Cz 49 When the modified siloxane fluid from above is re- (c) A mixture containing 20 percent by weight of a acted as in Example 1 with toluene diisocyanate, there is copolymer of 3-b t l th 1 il and /1 mformed the polysiloxane isocyanate structure 5510x3116 f th composition e t t MezSi (OSi)45CH OH SOHzCNC Me Me Me ir=c= 2 H0 S iO S iO H The fluid obtained by the above sequence of operations hm will vulcanize to a flexible rubbery solid when exposed to CEHZOZCH 2 ((IJHMCHS 98 moisture. 50

Example 9 Equivalent results are obtained when the following diand percent by weight of a 3,3,3-trifluoropropylmethylorganopolysiloxanes-are substituted for the dimethylpolypolysiloxane fluid of the structure siloxane of Example 5.

(a) A phenylmethylpolysiloxane of the average formula ll HO SiO H z zc s HO s10 H The polysiloxane isocyanate formed is a mixture containing units of the structure H 0 Me Me Me: Me Me M62 Me Me 0 H Me-C I I( J-I ICH2(JHCHZS iO S iO S iO S iCHz(3HCHrI I-( il @l\le (IJHZ $132 I O=O=N N=C=O l CH2CECH 2 (CH2)10CH3 98 l3 l4- and I? 5]) Me Me Mez Me Meg BI Ie hl'lefl) 1'1 Me--N-oNcH2oHoH2si0 SIiO SiOH 2CHCHr N-GN--Me CHzCHiCFs ion I O=C=N N=C=O (d) A copolymer containing (2-phenylethyl)methyl- Example 11 siloxane units, cyclopentenylmethylsiloxane units and ethylmethylsiloxane units of the average composition will produce a polysiloxane isocyanate of the average composition A modified polysiloxane is formed when the above amine is added to the siloxane fluid of Example 3 I Mes [Mez IiS i Sh) 44H] by a platinum catalyzed addition, having the average formula which in turn, when reacted with an excess of hexamethylenediisocyanate and the un reacted diisocyanate removed, will provide a polysiloxane isocyanate of the average formula H l I I II Me Miez M82] HSi (OSDzaOSiH a which, when further reacted with propargyl alcohol in the presence of a platinum catalyst forms a modified polysiloxane fluid of the structure Me: Me; HO CH2CH=CH K )2a0SiCH=CHCH2OH]a When the above compound is reacted with an excess of hexamcthylenediisocyanate and the unreacted diisocyanate thereafter removed, there is obtained a polysiloxane isocyanate of the structure The product above, when mixed with 1 percent by weight of dibutyltindilaurate, will cure to a flexible sltrong solid. Example 12 When the monoallylether of 2-butene-1,4-diol is substituted for the allyloxypropanol of Example 1 there is obtained a modified polysiloxane fluid of the average formula Me: 1:462 MeSiKOSDmOSKCHz)3QCH2CH=CHCH2OH]3 A polysiloxane isocyanate which will cure on exposure to moisture to a tack-free flexible solid is formed when the modified polysiloxane above is reacted with cy'clo-' hexane-lA-diisocyanate of the average formula Me: U

which, on exposure to moisture cures to a strong flexible solid. I

Similar results are obtained to the above when the monoallyl ether of 2-butyne-l,4-diol is substituted for the mouoallyl ether of 2-butene-1,4-diol. The polysiloxane after removed, there remains a polysiloxane isocyanate lsocyanate of the average formula of the formula Me: Me: (6 lil /CH2-CH2 MieSiKOSDzsOSKOHzhOGHnOECG1I2OC-NOH CH-N=C=O];

is thereby formed, which will cure to a flexible tack-free H rubber on exposure to moisture. 0( i-(OHz)4i I=O=-0 Example 13 i When methacrylic acid is added to the siloxane fluid Si of Example 2 using a platinum catalyst, and the resulting Me cqmpound treated first thlonyi Chlonde This product when mixed with one percent of dibutylw th anhydrous ammonia n anhydrous ether, them 18 tindiiaurate, will cure at room temperature to a tack-free tamed a modified polysiloxane fluid of the average flexible solid structure 15 Example 16 fi Y R When the compound HZNC CHCHg-Si[(0 Si) 36CH2CHCNH2]2 CH-CH2 when further reacted with toluene diisocyanate as in Ex- \OHOH ample 1 will form a polysiloxane isocyanate of the average formula CH-CHB i This fluid will cure to a flexible tack-free solid when is substituted for allyloxypropanol in the process of Exexposed to moisture. ample 3, the resulting polysiloxane isocyanate is of the average formula I Example 14 haea $1 When the experiments of Example 3 are repeated, ex- Mezsi )2z C cept substituting allyl mercaptan for ailyloxypropanel, there is obtained a polysiloxane isocyanate of the average formula which cures to a flexible tack-free solid on exposure to M62 0 H i moisture. V MezSi (OSii)u(OH )aS I I -Me {Example 17 I When methylamine 1s substituted for ammonia and a =g=o 2 diisocyanate of the structure which will cure to a tack-free flexible solid on exposure M6 M6 to moisture.

Example 15 When metavinylphenol is added to a polysiloxane fluid substituted for toluene diisocyanate in Example 13 there of the structure is obtained a polysiloxane isocyanate of the structure Me Me Me 0 Me Me Me; Me (I? Mei) 11 which cures to a tack-free elastomer on exposure to mois- O ture.

1 SOME Example 18 Me i in the presence of a platinum catalyst, there is formed When a polysiloxane fluid of the structure a modified polysiloxane of the structure Me Me; OH 1? i CH CClSi (OSi)-ioOH 2 s1 (OSi)a.'s-CHZOH is substituted for the fluid of Example 6 and hexarnethyll ene dusocyanate substituted for toluene dnsocyanate of W1 nenfhls PmduCt 1S reacted with an excess 0f that example, there is obtained the polysiloxane diisocybutanediisocyanate and the unreacted diisocyanate thereanate of the structure Mali Me; Me Me Me "CHz=CClS l (OSDAGOSiCHZCHCH2"-N-CN(CH2)6N C O 1 7 18 which when exposed to moisture will cure to a flexible Y is a divalent hydrocarbon radical free of aliphatic strong elastomer. unsaturation having at least four carbon atoms That which is claimed is: therein,

1. An organosiloxane isocyanate of the structure ais an integer including 0,

R is selected from the group consisting of monovalent m is an integer from to 2 inclusive, hydrocarbon radicals and monovalent halohydrocarn is an integer from 0 to 1 inclusive, bon radicals, m+n is an integer from 0 to 3 inclusive,

W is a divalent organic radical having at least two carp is an integer such that the sum of all p values in the bon atoms therein, connected to silicon by a siliconmolecule averages at least that given by the equation to-carbon bond and to the remainder of the mole- (sum of all p) =5 (3 wherein m is as above decule through another carbon atom of the radical and fined, and being selected from the group consisting of hydro- (2) a filler. carbons, hydrocarbon thioethers, hydrocarbon esters, 6. An organopolysiloxane isocyanate of the structure R is a divalent aliphatic radical having two to four R is selected from the group consisting of monovalent carbon atoms such that no carbon atom shall have hydrocarbon radicals and monovalent halohydromore than one oxygen atom attached thereto, carbon radicals,

X is selected from the group consisting of O, W is a divalent organic radical having at least two S, carbon atoms therein, connected to silicon by a sili- O H O R R con-to-carbon bond and to the remainder of the II I II I I molecule through another carbon atom of the radical T C N and N and being selected from the group consisting of hy- Whersln R 15 as abOVe defined, drocarbons, hydrocarbon thioethers, hydrocarbon Y is a divalent hydrocarbon radical free of aliphatic 39 esters d hydrocarbon tertiary amines,

unsaturation having at least four Carbon atoms R is a divalent aliphatic radical having two to four therein, carbon atoms such that no carbon atom shall have ll is an integer including more than one oxygen atom attached thereto, 5 is an integer frc'm 0 i0 1 inclusive, X is selected from the group consisting of -O-, m is an integer from O to 2 inclusive, g... n is an integer from 0 to 1 inclusive, 0 H O R R m-I-n is an integer from 0 to 3 inclusive, II I II I p is an integer such that the sum of all p values in the herein R is as above defined 1e ul av ra es at 1 ast that men b the e ua- W 2:; Whirein as agave 40 Y 1s a divalent hydrocarbon radical free of ahphatic dgfined unsaturation having at least four carbon atoms there- 2. An organosiloxane isocyanate accordingto claim 1 V wherein R is methyl, W is trimethylene, a is 0, X is dia 18 an Integer mcludmg b is an integer from 0 to 1 inclusive, and

valent oxygen and Y is C6H3 (CH3) p is an integer from 20 to 200 inclusive.

3. An organosiloxane isocyanate according to claim 1 7. The composition of matter consisting essentially of wherein R methyl W 15 mmethylene R 15 (1) the organopolysiloxane isocyanate of claim 2 and (2) CH CH(CH a fillen a is l, X is divalent oxygen and Y is C H (CH 8. The cured flexible solid obtained from the compo- 4. An organosiloxane isocyanate a cording to claim 1 sition of claim 1 by exposure of the said. composition to wherein R is trifluoropropyl and methyl, W is trimethylmoisture, ene, a is 0, X is divalent oxygen and Y is -'f- 6 3 (C 3)-- 9. The cured composition obtained by exposing the 5. A composition of matter consisting essentially of composition of claim 2 to moisture. (1) an organosiloxane isocyanate of the structure 10. The cured composition obtained by exposing the Rm R2 0 H [0:C=NYi IiiXi,(it o).,W],,di[ odi),,--W(oR),,-X1rihlhY-N==o=0]i wherein composition of claim 3 to moisture.

R'is selected from the group consisting of monovalent 11. The cured composition'obtained by exposing the hydrocarbon radicals and monovalent halohydrocarcomposition of claim 4 to moisture. bon radicals, 12. The cured composition obtained by exposing the W is a divalent organic radical having at least two composition of l i 5 t ist carbon atoms therein, connected to silicon by a 13. The cured composition obtained byexposing the silicon-to-carbon bond and to the remainder of the composition of claim 6 to moisture. molecule through another carbon of the radical and 14. The cured composition obtained by, exposing the being selected from the group consisting of hydrocomposition of claim 7 to moisture. carbons, hydrocarbon thioethers, hydrocarbon esters, i a and hydrocarbon tertiary amines, References Cited by the Examiner R is a divalent aliphatic radical having two to four UNITED STATES PATENTS carbon atoms such that no carbon atom shall have more than one oxygen atom attached thereto, 252759O 10/50 Spewr 260-465 X is selected from the group consisting of -O-, FOREIGN PATENTS S-, 580,932 8/59 Canada.

0 o R R I g L and t MURRAY TILLMAN, Primary Examiner.

wherein R is as above defined, JOSEPH L. SCHOFER, Examiner. 

1. AN ORGANOSILOXANE ISOCYANATE OF THE STRUCTURE
 8. THE CURED FLEXIBLE SOLID OBTAINED FROM THE COMPOSITION OF CLAIM 1 BY EXPOSRE OF THE SAID COMPOSITION TO MOISTURE. 